Solution for: browser won’t load certain websites on a Mac

August 29, 2014 Denis Kutlubaev Leave a comment

In many cases, this problem occurs, when a browser can’t resolve a host. I.e. it cannot find an IP address for a certain domain name in DNS servers. This happens, when your provider is too slow in updating DNS entries from all over the world when they are changed by administrators of web sites.

In case your browser won’t load certain websites, you can try to add DNS entries for those sites manually in your hosts file. To do this do the following:

1. In Terminal type the following:

~: $ sudo vim /etc/hosts

1	~: $ sudo vim /etc/hosts

so that you begin to edit your hosts file

2. Enter the password for your admin user on your mac.

3. Press “I” to enter Insert mode in Vim.

4. Go to the end of file and type IP addresses and corresponding domain names:

78.47.91.3      ladby.ru
78.47.91.3      anna.ladby.ru
78.47.91.3      www.ladby.ru
78.47.91.3      club.ladby.ru

78.47.91.3 ladby.ru

78.47.91.3 anna.ladby.ru

78.47.91.3 www.ladby.ru

78.47.91.3 club.ladby.ru

5. Press Esc. And type “:wq” to save and exit from vim.

6. Ready! You can now try to open your web sites.

If you don’t know IP address for your site, you can ping it on some other computer to determine the IP address or use web sites for this purpose to determine IP by domain name. For example, this one.

Android

On TextView Hints and StringUtils.isBlank

August 25, 2014 Denis Kutlubaev Leave a comment

I had a problem caused by setting empty or blank strings to the TextView and AutoCompleteTextView – hints were invisible after that. So I decided to check strings, that are set, if they were not only empty, but also not blank. I used StringUtils.isBlank instead of StringUtils.isEmpty: it works much better now, and hints are always visible. If you don’t still use StringUtils, I highly recommend you to do. This is a Gradle import for a library that contains them:

dependencies {
    compile 'org.apache.commons:commons-lang3:3.0.+'
}

dependencies {

compile 'org.apache.commons:commons-lang3:3.0.+'

}

String keywordsForTextView = searchHistoryItem.getKeywords();
if ( StringUtils.isBlank(keywordsForTextView) ) {
      Resources res = context.getResources();
      keywordsForTextView = res.getString(R.string.no_keywords);
}

String keywordsForTextView = searchHistoryItem.getKeywords();

if ( StringUtils.isBlank(keywordsForTextView) ) {

Resources res = context.getResources();

keywordsForTextView = res.getString(R.string.no_keywords);

}

And another example with AutoCompleteTextView:

public void setKeywords(String keywords) {
   this.keywords = keywords;
   if (StringUtils.isNotBlank(keywords)) {
      Log.v(Helper.TAG, "Setting keywords to the keywordAutoCompleteTextView: " + keywords);
      keywordAutoCompleteTextView.setText(keywords);
   }
}

public void setKeywords(String keywords) {

this.keywords = keywords;

if (StringUtils.isNotBlank(keywords)) {

Log.v(Helper.TAG, "Setting keywords to the keywordAutoCompleteTextView: " + keywords);

keywordAutoCompleteTextView.setText(keywords);

}

Here is some information on how isNotEmpty and isNotBlank are working.

Title of this article: On Android TextView and AutoCompleteTextView Hint and StringUtils.isBlank and .isEmpty

Web Development

How to find an e-mail in Ubuntu, that appears in logs

August 21, 2014 Denis Kutlubaev Leave a comment

I had a problem on Ubuntu server. Some guy has added his e-mail somewhere and the server tried to send him e-mails. So Google responded, that it was spam and blocked them. I have searched using grep in logs this way:

/var/log # grep -n "guys_name@gmail.com" *

1	/var/log # grep -n "guys_name@gmail.com" *

And got this kind of entries in mail.log and others:

syslog.1:6538:Aug 21 03:39:54 lovecakes postfix/smtp[24625]: A49A315A951: to=<guys_name@gmail.com>, relay=gmail-smtp-in.l.google.com[64.233.165.27]:25, delay=2.9, delays=1.2/0/0.46/1.2, dsn=2.0.0, status=sent (250 2.0.0 OK 1408585194 wr8si36296852lbc.79 - gsmtp)
syslog.1:6864:Aug 21 04:32:18 lovecakes postfix/smtp[24949]: A04A215A951: to=<guys_name@gmail.com>, relay=gmail-smtp-in.l.google.com[2a00:1450:4010:c08::1a]:25, delay=12, delays=10/0.01/0.4/1.6, dsn=2.0.0, status=sent (250 2.0.0 OK 1408588338 t1si36397231laj.89 - gsmtp)
syslog.1:6990:Aug 21 04:50:56 lovecakes postfix/smtp[25071]: 0D54315A951: to=<guys_name@gmail.com>, relay=gmail-smtp-in.l.google.com[2a00:1450:4010:c08::1b]:25, delay=3.1, delays=1.4/0/0.34/1.3, dsn=5.7.1, status=bounced (host gmail-smtp-in.l.google.com[2a00:1450:4010:c08::1b] said: 550-5.7.1 [2a01:4f8:d15:1fc4::2      12] Our system has detected that this 550-5.7.1 message is likely unsolicited mail. To reduce the amount of spam sent 550-5.7.1 to Gmail, this message has been blocked. Please visit 550-5.7.1 http://support.google.com/mail/bin/answer.py?hl=en&answer=188131 for 550 5.7.1 more information. c2si36483814lac.0 - gsmtp (in reply to end of DATA command))

syslog.1:6538:Aug 21 03:39:54 lovecakes postfix/smtp[24625]: A49A315A951: to=<guys_name@gmail.com>, relay=gmail-smtp-in.l.google.com[64.233.165.27]:25, delay=2.9, delays=1.2/0/0.46/1.2, dsn=2.0.0, status=sent (250 2.0.0 OK 1408585194 wr8si36296852lbc.79 - gsmtp)

syslog.1:6864:Aug 21 04:32:18 lovecakes postfix/smtp[24949]: A04A215A951: to=<guys_name@gmail.com>, relay=gmail-smtp-in.l.google.com[2a00:1450:4010:c08::1a]:25, delay=12, delays=10/0.01/0.4/1.6, dsn=2.0.0, status=sent (250 2.0.0 OK 1408588338 t1si36397231laj.89 - gsmtp)

syslog.1:6990:Aug 21 04:50:56 lovecakes postfix/smtp[25071]: 0D54315A951: to=<guys_name@gmail.com>, relay=gmail-smtp-in.l.google.com[2a00:1450:4010:c08::1b]:25, delay=3.1, delays=1.4/0/0.34/1.3, dsn=5.7.1, status=bounced (host gmail-smtp-in.l.google.com[2a00:1450:4010:c08::1b] said: 550-5.7.1 [2a01:4f8:d15:1fc4::2 12] Our system has detected that this 550-5.7.1 message is likely unsolicited mail. To reduce the amount of spam sent 550-5.7.1 to Gmail, this message has been blocked. Please visit 550-5.7.1 http://support.google.com/mail/bin/answer.py?hl=en&answer=188131 for 550 5.7.1 more information. c2si36483814lac.0 - gsmtp (in reply to end of DATA command))

For a while I couldn’t find a problem place and didn’t know, where to fix. I tried to list cron jobs:

for user in $(cut -f1 -d: /etc/passwd); 
do 
  crontab -u $user -l; 
done

for user in $(cut -f1 -d: /etc/passwd);

crontab -u $user -l;

done

But without a success.

Finally, I did search using grep recursively and found some files, where this e-mail appeared:

root@lovecakes /home # grep -r 'guys_name' /etc
Binary file /etc/postfix/transport.db matches
Binary file /etc/postfix/recipient_bcc.db matches

root@lovecakes /home # grep -r 'guys_name' /etc

Binary file /etc/postfix/transport.db matches

Binary file /etc/postfix/recipient_bcc.db matches

Because it was in *.db files, I couldn’t fix it by just editing config files in PostFix.

And because PostFix is not used in the server, I just removed it:

# sudo apt-get purge postfix

1	# sudo apt-get purge postfix

Web Development

To install e-mail server on Ubuntu or just to use web mail services?

August 21, 2014 Denis Kutlubaev 1 Comment

My goal was to create e-mails like user@mydomain.ru and use these e-mails outside the server, by accessing them using IMAP and SMTP protocols.

Unfortunately, instead of trying to find the most beautiful, fast and feature-rich solution, I decided to setup an e-mail server on Ubuntu on the basis of PostFix (running on a v-server at Hetzner hosting). It is a private server, that doesn’t support e-mail serving by default – you have to setup it yourself. Trying to create something great on Ubuntu for a not red eye Linux geek is like trying to build Boeing 747 by yourself. But I decided to accept this challenge without thinking much and wasted a ton of time as a result. I tried hard for 2 days and all that I had achieved is e-mail forwarding from my server to the Google e-mail.

I tried to use DoveCot and Courier to enable IMAP or POP, but without a success. I couldn’t connect Apple Mail to the resulting e-mail server and make it work. I worked with a lot of configuration files, tried to setup correctly SASL, etc. but at the end I understood, that this is a too hard work to create just an e-mail server. I understood that this must not be a correct way to go. Look for instance at this tutorial. Of course, it is a possiblity, but it works with a very little features and very hard to achieve good functionality. Look at these terrible configs:

I didn’t want to become a Linux geek with red eyes, but I did… The way of creating e-mail server on Ubuntu from scratch appeared to be absolutely unproductive because of tons of problems during configuration and a little number of features at the result. After some time I decided to look at Yandex and Google e-mail services for corporate businesses, when you use their e-mail servers by redirecting from your own domain. And I am glad, I decided to try! At the end, I created the goal e-mail server using Yandex. Yandex service is called a Mail for domain.

All I had to do – is to setup DNS entries, MX entries particularly and put one file to the root folder of the site.

Look, how nicely it works now both on Apple Mail and via Web Interface on Yandex:

And here is how to setup IMAP and SMTP on Apple Mail or any other E-mail client.

Web Development

Shell scripts that copy, rename files and resize, crop images

August 15, 2014 Denis Kutlubaev Leave a comment

I have written a bunch of shell scripts for my Mac, that do a lot of work automatically.

First script renames all files in a folder sequentially and gives the names with numbers starting from 64:

a=64
for i in *.jpg; do
    new=$(printf "%d.jpg" ${a})
    mv ${i} ${new}
    let a=a+1
done

a=64

for i in *.jpg; do

new=$(printf "%d.jpg" ${a})

mv ${i} ${new}

let a=a+1

done

The second script creates copies of those files and adds “_mini” to the file name. It creates future miniatures of images.

for f in *.jpg; do
    cp -v $f ${f%.jpg}_mini.jpg
done

for f in *.jpg; do

cp -v $f ${f%.jpg}_mini.jpg

done

The third script deletes all files in a folder that do not match a pattern with “_mini” word:

shopt -s extglob
rm !(*_mini.jpg)

1 2	shopt -s extglob rm !(*_mini.jpg)

And the last script crops images to the given size:

for i in *.jpg
	do 
		convert $i -gravity Center -crop 287x185+0+0 $(basename $i .jpg).jpg 
	done

for i in *.jpg

convert $i -gravity Center -crop 287x185+0+0 $(basename $i .jpg).jpg

done

It is also possible to resize images in other ways, for example percentage:

for i in *.jpg; do 
convert $i -resize 10% $(basename $i .jpg).jpg; done

1 2	for i in *.jpg; do convert $i -resize 10% $(basename $i .jpg).jpg; done

Here are the full instructions for ImageMagick.

Here is an information on copying files.

And here is an information on deleting by pattern.

Finally we get something like this:

Final script:

cd "/Users/Denis/Desktop/Cakes"

#Renaming
a=1
for i in *.jpg; do
    new=$(printf "%d.jpg" ${a})
    mv ${i} ${new}
    let a=a+1
done

#Create copies
for f in *.jpg; do
    cp -v $f ${f%.jpg}_mini.jpg
done

#Delete original images
shopt -s extglob
rm !(*_mini.jpg)

#Resize, create miniatures
for i in *.jpg
do
	convert $i -resize 287 $i 
	convert $i -gravity North -crop 287x185+0+0 $i
done

cd "/Users/Denis/Desktop/Cakes"

#Renaming

a=1

for i in *.jpg; do

new=$(printf "%d.jpg" ${a})

mv ${i} ${new}

let a=a+1

done

#Create copies

for f in *.jpg; do

cp -v $f ${f%.jpg}_mini.jpg

done

#Delete original images

shopt -s extglob

rm !(*_mini.jpg)

#Resize, create miniatures

for i in *.jpg

convert $i -resize 287 $i

convert $i -gravity North -crop 287x185+0+0 $i

done

This script rename files with spaces in their file names:

#!/bin/bash
SAVEIFS=$IFS
IFS=$(echo -en "\n\b")
a=1
for i in *.mp3; do
	echo "$i"
	printf "%d.mp3\n" ${a}
    new=$(printf "%d.mp3" ${a})
    mv "$i" ${new}
    let a=a+1
done
IFS=$SAVEIFS

#!/bin/bash

SAVEIFS=$IFS

IFS=$(echo -en "\n\b")

a=1

for i in *.mp3; do

echo "$i"

printf "%d.mp3\n" ${a}

new=$(printf "%d.mp3" ${a})

mv "$i" ${new}

let a=a+1

done

IFS=$SAVEIFS

Here you can read more about treating spaces in file names in bash scripts.

Web Development

Apache config file with multiple VirtualHosts

August 13, 2014 Denis Kutlubaev 1 Comment

I wanted to be able to open sites like *.ladby.ru and *.lovecakes.ru besides main sites ladby.ru and lovecakes.ru. This is how I solved this problem – by editing Apache config file, making it much simpler and by using ServerNames instead of ServerAliases.

<VirtualHost *:80>
  	ServerName www.lovecakes.ru
  	DocumentRoot /var/www/lovecakes.ru/public/
</VirtualHost>

<VirtualHost *:80>
	ServerName galina.lovecakes.ru
  	DocumentRoot /var/www/galina.lovecakes.ru/public/
</VirtualHost>

<VirtualHost *:80>
	ServerName www.ladby.ru
  	DocumentRoot /var/www/ladby.ru/public/
</VirtualHost>

<VirtualHost *:80>
	ServerName ladby.ru
  	DocumentRoot /var/www/ladby.ru/public/
</VirtualHost>

<VirtualHost *:80>
 	ServerName club.ladby.ru
  	DocumentRoot /var/www/club.ladby.ru/public/
</VirtualHost>

ServerName www.lovecakes.ru

DocumentRoot /var/www/lovecakes.ru/public/

</VirtualHost>

ServerName galina.lovecakes.ru

DocumentRoot /var/www/galina.lovecakes.ru/public/

</VirtualHost>

ServerName www.ladby.ru

DocumentRoot /var/www/ladby.ru/public/

</VirtualHost>

ServerName ladby.ru

DocumentRoot /var/www/ladby.ru/public/

</VirtualHost>

ServerName club.ladby.ru

DocumentRoot /var/www/club.ladby.ru/public/

</VirtualHost>

And this is how the tree looks like:

Do not forget to reload Apache after editing conf file, which lies here: /etc/apache2/sites-available:

# sudo /etc/init.d/apache2 reload

1	# sudo /etc/init.d/apache2 reload

So, now the following sites are working:
club.ladby.ru
ladby.ru
www.ladby.ru
lovecakes.ru
www.lovecakes.ru
galina.lovecakes.ru

Android

I am now a Friend of Eclipse

August 7, 2014 Denis Kutlubaev 1 Comment

I was awarded a status of a Friend of Eclipse.

I like Eclipse, since it is free and powerful. I was using it for Android development for free and created a lot of staff, that is why I decided to help Eclipse team. Although I have moved to Android Studio recently, currently I use Eclipse Luna for developing web applications for Google App Engine.

Web Development

Solving Google App Engine : 500 Server Error

August 7, 2014 Denis Kutlubaev 1 Comment

I started to learn Google App Engine. Everything was perfect – tutorials, easiness of testing on development server before I wanted to deploy it on server. I knew that I had to use Java 7 instead of Java 8, which is currently supported by App Engine, but didn’t know, where I should change it easily to make this happen, since I used Maven.

This error happened to me:
Server Error The server encountered an error and could not complete your request. Please try again in 30 seconds.

In errors of my app on App Engine Console I saw this:
Uncaught exception from servlet java.lang.UnsupportedClassVersionError: org/apache/jsp/guestbook_jsp : Unsupported major.minor version 52.0 at com.go

You can see logs this way:

You can check your java version:

    $ java -version

1	$ java -version

This is solution:

Then go to profile:

    $ vim ~/.bash_profile

1	$ vim ~/.bash_profile

And change your JAVA_HOME variable:

    export JAVA_HOME=`/usr/libexec/java_home -v 1.7`

1	export JAVA_HOME=`/usr/libexec/java_home -v 1.7`

Update that variable:

    $ source ~/.bash_profile

1	$ source ~/.bash_profile

And now rebuild your AppEngine project and redeploy it on server:

    $ mvn clean install
    $ cd guestbook-ear
    $ mvn appengine:update

$ mvn clean install

$ cd guestbook-ear

$ mvn appengine:update

Now check your application on browser: https://your_app_id.appspot.com/

Android

Gradle build file for a project with Android Annotations

August 5, 2014 Denis Kutlubaev Leave a comment

There is a sample Gradle build file for a project with Android Annotations. This is pretty complicated stuff, that was achieved with a lot of my blood, so I decided to post it here, so that you can use it to try to find your mistakes. Android Annotations library is loaded with apt. The position of every setting is important. There is also a trick to avoid Lint errors and a custom task to run app via command line.

I used Gradle 1.12 and Android Studio 0.8.4 with Android SDK 20, Android Build Tools 20.0 and Android Plugin 0.12.+.

buildscript {
    repositories {
        mavenCentral()
    }

    dependencies {
        classpath 'com.android.tools.build:gradle:0.12.+'
        classpath 'com.neenbedankt.gradle.plugins:android-apt:1.3'
    }
}

repositories {
    mavenCentral()
    mavenLocal()
}

apply plugin: 'com.android.application'
apply plugin: 'android-apt'
def AAVersion = '3.0.1'

dependencies {
    apt "org.androidannotations:androidannotations:$AAVersion"
    compile "org.androidannotations:androidannotations-api:$AAVersion"
    compile "com.android.support:support-v4:18.0.+"
    compile "com.android.support:appcompat-v7:18.0.+"
    compile 'org.apache.commons:commons-lang3:3.0.+'
    compile fileTree(dir: 'libs', include: '*.jar')
}

apt {
    arguments {
        androidManifestFile variant.processResources.manifestFile
        resourcePackageName "ru.rabota.app2"
    }
}

android {
    compileSdkVersion 20
    buildToolsVersion '20.0.0'

    defaultConfig {
        minSdkVersion 10
        targetSdkVersion 20
        versionCode 17
        versionName "2.4.2"
    }

    sourceSets {
        main {
            manifest.srcFile 'AndroidManifest.xml'
            java.srcDirs = ['src']
            resources.srcDirs = ['src']
            aidl.srcDirs = ['src']
            renderscript.srcDirs = ['src']
            res.srcDirs = ['res']
            assets.srcDirs = ['assets']
        }

        androidTest.setRoot('tests')
    }

    lintOptions {
        abortOnError false
    }
}

task appStart(type: Exec, dependsOn: ':installDebug') {
    // linux 
    commandLine 'adb', 'shell', 'am', 'start', '-n', 'ru.rabota.app2/ru.rabota.intro.IntroActivity'

    // windows
    // commandLine 'cmd', '/c', 'adb', 'shell', 'am', 'start', '-n', 'com.alwawee.multiverse/com.alwawee.main.MainActivity'      
}

buildscript {

repositories {

mavenCentral()

}

dependencies {

classpath 'com.android.tools.build:gradle:0.12.+'

classpath 'com.neenbedankt.gradle.plugins:android-apt:1.3'

}

repositories {

mavenCentral()

mavenLocal()

}

apply plugin: 'com.android.application'

apply plugin: 'android-apt'

def AAVersion = '3.0.1'

dependencies {

apt "org.androidannotations:androidannotations:$AAVersion"

compile "org.androidannotations:androidannotations-api:$AAVersion"

compile "com.android.support:support-v4:18.0.+"

compile "com.android.support:appcompat-v7:18.0.+"

compile 'org.apache.commons:commons-lang3:3.0.+'

compile fileTree(dir: 'libs', include: '*.jar')

}

apt {

arguments {

androidManifestFile variant.processResources.manifestFile

resourcePackageName "ru.rabota.app2"

}

android {

compileSdkVersion 20

buildToolsVersion '20.0.0'

defaultConfig {

minSdkVersion 10

targetSdkVersion 20

versionCode 17

versionName "2.4.2"

}

sourceSets {

main {

manifest.srcFile 'AndroidManifest.xml'

java.srcDirs = ['src']

resources.srcDirs = ['src']

aidl.srcDirs = ['src']

renderscript.srcDirs = ['src']

res.srcDirs = ['res']

assets.srcDirs = ['assets']

}

androidTest.setRoot('tests')

}

lintOptions {

abortOnError false

}

task appStart(type: Exec, dependsOn: ':installDebug') {

// linux

commandLine 'adb', 'shell', 'am', 'start', '-n', 'ru.rabota.app2/ru.rabota.intro.IntroActivity'

// windows

// commandLine 'cmd', '/c', 'adb', 'shell', 'am', 'start', '-n', 'com.alwawee.multiverse/com.alwawee.main.MainActivity'

}

Alwawee

Monthly Archives: August 2014

Solution for: browser won’t load certain websites on a Mac

On TextView Hints and StringUtils.isBlank

How to find an e-mail in Ubuntu, that appears in logs

To install e-mail server on Ubuntu or just to use web mail services?

Shell scripts that copy, rename files and resize, crop images

Apache config file with multiple VirtualHosts

I am now a Friend of Eclipse

Solving Google App Engine : 500 Server Error

Gradle build file for a project with Android Annotations

iOS Development